Method for preparing storage-stable fast-drying multi-component aqueous coating compositions and coatings derived therefrom

ABSTRACT

A storage stable, fast drying multi-component aqueous coating composition which includes an anionically stabilized binder polymer, a vinylamine polymer and a volatile base is disclosed. A method for using the aqueous coating composition to produce a coating on the surface of a substrate is further disclosed, along with the coating produced.

[0001] The present invention relates to storage-stable fast-dryingmulti-component aqueous coating compositions and fast-drying coatingsmade therefrom.

[0002] Used herein, the term “multi-component” refers to aqueous coatingcompositions having two or more components applied to a substrate in oneor more steps.

[0003] One of the many important features of coating compositions is thespeed at which they dry on the surface of a given substrate afterapplication. For instance, the drying speed of a traffic paint dictatesthe length of the period of disruption to road traffic duringapplication of that paint to road surfaces, and subsequent drying. Thetrend is to demand shorter and shorter disruptions of traffic flow, andto meet this demand by using faster drying coating compositions.

[0004] Solvent-based fast-drying coating compositions are based onorganic polymeric binders dissolved, suspended or otherwise dispersed inrelatively low-boiling organic solvents. Low-boiling volatile organicsolvents evaporate rapidly after application of the coating compositionon the road to provide the desired fast drying characteristics of afreshly applied road marking. However, in addition to releasing volatileorganic solvents into the environment, this type of paint formulationtends to expose workers to the vapors of the organic solvents. Becauseof these shortcomings and increasingly stringent environmental mandatesfrom governments and communities, it is highly desirable to develop moreenvironmentally friendly coating compositions while retaining fastdrying properties and/or characteristics.

[0005] A more environmentally friendly coating composition uses waterbased, i.e., aqueous, rather than solvent based, polymers or resins.Coating formulations, both solvent based and aqueous, include binders.The terms “binder” and “binder polymer” used herein refer to polymersthat are included in the coating composition and that participate infilm formation, becoming part of the resultant film. Binder polymerstypically have glass transition temperature (Tg) values in the range−10° C. to 70° C. because those having Tg values below −10° C. tend tohave poor resistance to dirt pick-up and those having Tg values above70° C. usually display diminished ability to form films. In certainapplications, however, the lower limit for Tg can be even lower than−10° C. For example, the binder polymers used in roof coatings can haveglass transition temperatures as low as −40° C. Primarily due to acombination of high boiling point, high latent heat of vaporization,high polarity, and strong hydrogen bonding of water, drying times of thecoatings formed by application of an aqueous coating composition to asubstrate surface are generally longer than those exhibited by theorganic solvent based coatings. The drying time strongly depends on therelative humidity of the atmosphere in which the coating compositionsare applied. An aqueous coating composition may take several hours ormore to dry in high humidity. The problem of retarded drying rate isespecially aggravated for thick film (greater than about 500μ) coatings.Long drying times severely limit the desirability of using aqueouscoating compositions, particularly traffic paints, the drying times ofwhich directly effect the length of traffic disruptions.

[0006] U.S. Pat. No. 5,804,627 discloses methods of producing fastdrying coatings on the surfaces of substrates. The methods includeapplying to those surfaces an aqueous coating composition including ananionically stabilized emulsion polymer having a Tg greater than about0° C., a polyamine functional polymer having from about 20% to about100% of the monomer units by weight containing an amine group, and anamount of volatile base sufficient to raise the pH of the composition toa point where essentially all of the polyamine functional polymer is ina non-ionic state. During and after application of the aqueous coatingcomposition to the surface of a substrate, the volatile base evaporateswith the result that the anionically stabilized polymer particles aredestabilized by protonated polyamine functional polymer, therebyaccelerating the drying rate of the coating. Although this systemaffords improvement in drying speeds, more efficient polyaminefunctional polymers are desired, imparting, for example, equivalentdrying speed at reduced levels in coating compositions.

[0007] WO 96/22338 discloses a fast drying aqueous coating compositionwhich derives its fast drying characteristic from a mechanism similar tothat of U.S. Pat. No. 5,804,627, except that the polyamine functionalpolymer is poly(ethyleneimine), also referred to herein as PEI. PEI isformed by polymerization of ethylene imine, a highly carcinogenicmonomer. The nitrogen content of PEI is higher than that of the otherconventional polyamine functional polymers, and this higher nitrogencontent offered the promise of higher drying efficiency. Unfortunately,the highly carcinogenic ethylene imine may be present, to some extent,in coating compositions containing PEI, so that such compositions are tobe avoided for environmental reasons. Extensive steps must also be takenduring manufacture of PEI to prevent exposure of workers to ethyleneimine. Moreover, although the promise of PEI in fast drying aqueouscoating compositions is that its high level of nitrogen, present asamino groups in the backbone of PEI, will translate into improved dryingrates, that promise cannot be fully realized for at least two reasons.First, as the volatile base evaporates from the coating, acidicsubstances become available to react with the amino groups, yet asignificant portion of those backbone amino groups will be less basicand be less accessible to the acidic substances due to the high degreeof steric hindrance from adjacent portions of the backbone of thepolymer. As a result, the formation of ammonium ions, an essential stepin the destabilization of the coating composition, does not occur forall of the amino groups of PEI. Second, and perhaps more importantly, asubstantial portion of the ammonium groups that do form from suchreaction are not fully accessible for interaction with, and subsequentdestabilization of, anionically stabilized emulsion polymers.

[0008] We have, surprisingly, found that vinylamine polymers are highlyefficient at producing storage stable, fast-drying aqueous coatingcompositions when those compositions include anionically stabilizedbinder polymer and volatile base. Unlike the amino groups of PEI, theamino groups of vinylamine polymers are fully available for protonationafter evaporation of the volatile amine with the result that vinylaminepolymers are more efficient (i.e., give more rapid drying at equalconcentrations) than PEI in spite of equal nitrogen content.

[0009] One aspect of the present invention relates to a storage stable,fast drying aqueous coating composition, said composition comprising:

[0010] (a) an anionically stabilized binder polymer;

[0011] (b) a vinylamine polymer having from 20% to 100% by weight ofamine functional units, based on total weight of said vinylaminepolymer; and

[0012] (c) an amount of volatile base sufficient to raise the pH of saidcomposition to a point where essentially all of the amine groups of saidvinylamine polymer are in a non-ionic state.

[0013] A second aspect of the present invention relates to a coating onthe surface of a substrate, said coating comprising:

[0014] (a) an anionically stabilized binder polymer; and

[0015] (b) a vinylamine polymer having from 20% to 100% by weight ofamine functional units, based on total weight of said vinylaminepolymer.

[0016] A third aspect of the present invention relates to a method ofproducing a coating on the surface of a substrate, said methodcomprising the steps of:

[0017] (i) applying to said surface a fast drying aqueous coatingcomposition comprising:

[0018] (a) an anionically stabilized binder polymer;

[0019] (b) a vinylamine polymer having from 20% to 100% by weight ofamine functional units, based on total weight of said vinylaminepolymer; and

[0020] (c) an amount of volatile base sufficient to raise the pH of saidcomposition to a point where essentially all of the amine groups of saidvinylamine polymer are in a non-ionic state;

[0021] (ii) evaporating said volatile base from said composition; and

[0022] (iii) drying said composition to form said coating.

[0023] A fourth aspect of the present invention relates to a method ofproducing a coating on the surface of a substrate, said methodcomprising the steps of:

[0024] (i) applying to said surface an aqueous composition comprising ananionically stabilized binder polymer;

[0025] (ii) applying to said surface an aqueous composition comprising avinylamine polymer having from 20% to 100% by weight of amine functionalunits, based on total weight of said vinylamine polymer; and

[0026] (iii) drying said coating.

[0027] The method of the fourth aspect of the present invention mayfurther include, in the aqueous composition comprising a vinylaminepolymer, a volatile base in an amount sufficient to deprotonate 20% to100% of the amine groups of the vinylamine polymer. When the volatilebase is present in the aqueous composition comprising a vinylaminepolymer, the method further includes the step of evaporating thevolatile base from the coating.

[0028] Additional aspects of the present invention include thecomposition of the first aspect and the method of the third aspectwherein the amount of volatile base is sufficient to deprotonate 20% to100% of the amine groups of said vinylamine polymer.

[0029] Used herein, the following terms have these definitions:

[0030] “Multi-component” refers to coating compositions having two ormore components which may be applied to a substrate in one or moresteps, and to the coatings made thereby.

[0031] The term “roadway” is used herein as a generic term and itincludes any indoor or outdoor solid surface that is or may be exposedto pedestrians, moving vehicles, tractors, or aircraft continuously,continually, or intermittently. Some non-limiting examples of a“roadway” include highways, streets, driveways, sidewalks, runways,taxiing areas, tarmac areas, parking lots, rooftops, and indoor floors(such as factory floors, or floors inside shopping malls). The surfacematerial may be masonry, tar, asphalt, resins, concrete, cement, stone,stucco, tiles, wood, polymeric materials and combinations thereof. Usedherein, the term “roadway” also embraces any surface of any substrateassociated with a roadway, including, for example, signs, barricades,medial strips, and signal devices.

[0032] A “roadway marking” is a coating on the surface of a “roadway”.

[0033] A “traffic paint” is a coating composition used to form a roadwaymarking. The traffic paints of the present invention are multi-componentaqueous coating compositions.

[0034] “Tg” is the “glass transition temperature” of a polymeric phase.The glass transition temperature of a polymer is the temperature atwhich a polymer transitions from a rigid, glassy state at temperaturesbelow Tg to a fluid or rubbery state at temperatures above Tg. The Tg ofa polymer is typically measured by differential scanning calorimetry(DSC) using the mid-point in the heat flow versus temperature transitionas the Tg value. A typical heating rate for the DSC measurement is 20°C./minute. The Tg of various homopolymers may be found, for example, inPolymer Handbook, edited by J. Brandrup and E. H. Immergut, IntersciencePublishers. The Tg of a polymer is calculated by using the Fox equation(T. G. Fox, Bull. Am. Physics Soc., Volume 1, Issue No. 3, page 123(1956)).

[0035] The term “fast-drying” is used herein to mean that a film (i.e.,the coating) of a so designated coating composition having a wet coatingthickness of 330 microns displays a dry-through time of less than twohours at 90% relative humidity at 23° C. The term “fast-drying aqueousbinder composition” refers to an aqueous dispersion of at least onebinder polymer that, when applied to a substrate, forms a coating havinga dry-through time conforming to the definition of “fast-drying” justgiven.

[0036] The term “amino group” refers to a functional group containingone or more amine nitrogen atoms, wherein an amine nitrogen atom is anitrogen atom bearing three substituents (e.g., hydrogen, or alkyl, or aportion of a polymer backbone) and a lone pair of electrons. The term“amine group” is used interchangeably with “amino group”.

[0037] The term “ammonium group” refers to a functional group containingone or more ammonium nitrogen atoms, wherein an ammonium nitrogen atomis a nitrogen atom bearing four substituents (e.g., hydrogen, or alkyl,or a portion of a polymer backbone) and having a positive charge. Theammonium nitrogen atom, along with the substituents attached to it isalso referred to as an “ammonium ion”

[0038] “Vinylamine polymer” refers to the unsubstituted“poly(vinylamine) homopolymer”, and is abbreviated “PVAm”. PVAmcopolymers are also useful in the present invention, as areN-substituted PVAm homopolymers and copolymers, and N,N-disubstitutedPVAm homopolymers and copolymers.

[0039] The “backbone” of a polymer chain is a collection of atomswherein each atom is directly attached to at least two other atoms thatform the actual links of the polymer chain. “Terminal” atoms of thebackbone are the only exception in that they are connected to only oneother atom that forms an actual link of the polymer chain. For example,when ethylene imine is polymerized, its nitrogen and both of its carbonsbecome part of the backbone of the polymer that is produced.

[0040] A “linear” polymer is a polymer having a backbone that is notbranched.

[0041] A “branched” polymer is a polymer having a backbone that hasother backbone segments (i.e., “branches”) attached to it. For example,the tertiary nitrogens of PEI serve as points of attachment (i.e.,“branch points”) for other backbone segments.

[0042] A “pendant” group is a group that is attached to the backbone ofa polymer, yet is not part of that backbone. For example, thepoly(vinylamine) backbone contains the two carbons of the vinylaminemonomer unit, but the amino group, —NH₂, of the vinylamine unit is apendant group. The amino group is said to be “pendant to” the backboneof the polymer.

[0043] “Molecular Weight” may be defined in several ways. Syntheticpolymers are almost always a mixture of many different molecularweights, i.e. there is a “molecular weight distribution”, abbreviated“MWD”. For a homopolymer, members of the distribution differ in thenumber of monomer units which they contain. This idea also extends tocopolymers. Given that there is a distribution of molecular weights, themost complete characterization of the molecular weight of a given sampleis the determination of the entire molecular weight distribution. Thischaracterization is obtained by separating the members of thedistribution and then quantitating the amount of each that is present.Once this distribution is at hand, there are several summary statistics,or moments, which can be generated from it to characterize the molecularweight of the polymer.

[0044] The two most common moments of the distribution are the “weightaverage molecular weight”, “M_(w)”, and the “number average molecularweight”, “M_(n)”. These are defined as follows:

M_(w)=Σ(W_(i)M_(i))/ΣW_(i)=Σ(N_(i)M_(i) ²)/ΣN_(i)M_(i)

M_(n)=ΣW_(i)/Σ(W_(i)/M_(i))=Σ(N_(i)M_(i))/ΣN_(i)

[0045] where:

[0046] M_(i)=molar mass of i^(th) component of distribution

[0047] W_(i)=weight of i^(th) component of distribution

[0048] N_(i)=number of chains of i^(th) component

[0049] and the summations are over all the components in thedistribution. M_(w) and M_(n) are typically computed from the MWD asmeasured by Gel Permeation Chromatography (see the ExperimentalSection).

[0050] The present invention requires that the aqueous coatingcomposition include as components a vinylamine polymer and ananionically stabilized emulsion polymer. Additionally, a volatile baseis included at a concentration sufficient to deprotonate the conjugateacid of the amino groups of the vinylamine polymer. Typically, 20 to 100mole % of the amino groups of the vinylamine polymer are deprotonated,preferably 60 to 100 mole %, more preferably 80 to 100 mole %, and mostpreferably 90 to 100 mole %. The presence of the vinylamine polymer indeprotonated form is necessary if the coating composition is to remainstable during storage, shipping, and handling. The deprotonated aminogroups do not bear a charge and, as such, do not interact with theanionic surfactant used to stabilize the emulsion polymer. Once theaqueous coating composition is applied to the surface of a substrate,the volatile base evaporates from the coating. As the volatile baseescapes, the amino groups of the vinylamine polymer become protonated toform a conjugate base which is an ammonium cation. The resultantcationic vinylamine polymer then interacts with the anionic surfactantto destabilize the emulsion polymer and, as a result, the coatingcomposition. In that way, accelerated drying is achieved. In the presentinvention, typically, 5 to 100 mole % of the amino groups of thevinylamine polymer become protonated, forming ammonium groups, as thevolatile base evaporates from the aqueous coating composition as itdries on the substrate surface to become a coating. Preferably thepercent of amino groups of the vinylamine polymer that become protonatedis 10 to 100 mole %, more preferably 40 to 100 mole %, and mostpreferably 80 to 100 mole %.

[0051] The vinylamine polymers of the present invention are uniquepolyamine functional polymers. Conventional polyamine functionalpolymers known to the art include, for example, aminoalky vinyl ethersand sulfides; (meth)acrylamides and (meth)acrylic esters, such asdimethylaminoethyl (meth)acrylate, bearing amine functionality; and PEI.Poly(vinylamine) homopolymer, PVAm, itself is higher in nitrogen contentthan all conventional polyamine functional polymers, with the exceptionof PEI, which has the same nitrogen content. Although PVAm and PEI havethe same number of amino groups, the amino groups of PVAm are primaryamine groups and, as such, are less sterically hindered, and morereadily accessible than those of PEI, with the result that protonatedPVAm is more efficient at destabilizing the anionic emulsion polymer toaccelerate drying. Upon application of the coating composition to thesurface of a substrate, the volatile amine evaporates, and the aminegroups of poly(vinylamine) homopolymer become protonated to formammonium salts. Due to its higher nitrogen content, the protonated pVAmthus formed has a higher charge density than conventional polyaminefunctional polymers. This higher charge density translates into higherefficiency when the protonated poly(vinylamine) homopolymer interactswith the centers of negative charge on the anionic surfactants. As aresult, destabilization of a given anionically stabilized latex may beachieved with reduced levels of pVAm. Further, this enhanced efficiencyis conferred to N-substituted and N,N-disubstituted vinylamine polymerswhen compared with other polyamine functional polymers having identicalsubstituents on nitrogen, and to vinylamine copolymers (co-pVAms) whencompared to other polyamine functional co-polymers having identicallevels of co-monomer present as polymerized units.

[0052] Only one other polyamine functional polymer offers a nitrogencontent as high as that of poly(vinylamine). That polymer ispoly(ethylene imine), referred to herein as PEI. PEI is formed by thepolymerization of ethylene imine, a highly carcinogenic monomer.Ethylene imine may, therefore, be present, to some extent, in coatingcompositions containing PEI, so that such compositions are to be avoidedfor environmental reasons. Moreover, there exist several importantstructural distinctions between the amino groups of PVAm and those ofPEI. When ethylene imine monomer reacts to form PEI, its nitrogen groupbecomes an integral part of the polymer backbone. In linear portions ofthe PEI backbone (i.e., portions where branching has not occurred) therepeat unit is —CH₂—CH₂—NH—, and a segment of the PEI backbonecontaining, for example, three of these linear repeat units has thisstructure:

—CH₂—CH₂—NH—CH₂—CH₂—NH—CH₂—CH₂—NH—.

[0053] Because each amine nitrogen of PEI is part of the backbone of thePEI polymer, each amine nitrogen has attached to it either one (i.e.,when the amino group occurs at the terminus of the backbone), two(secondary amino groups, i.e., neither a terminus, nor a branch point),or three (tertiary amino groups occurring as branch points) longsubstituents, each of which is a segment of polymer backbone. Thissituation is repeated for every nitrogen imbedded in the PEI backbone.For most of the amine nitrogen atoms of the PEI backbone, thesesubstituents may be a few, or tens, or hundreds of atoms long. It iswell known in the art of amine chemistry that multiple bulkysubstituents on the nitrogen of an amine reduce the reactivity of thelone pair of electrons on that nitrogen due to steric hindrance (see D.Barton and W. D. Ollis, Comprehensive Organic Chemistry, vol. 2, pp.34-36, Pergamon Press, New York, 1979). The space immediatelysurrounding the nitrogen lone electron pair becomes so crowded that theamino group is hindered from interacting with other chemical entities,and in fact the electron density of the lone electron pair decreases asthe geometry around the nitrogen becomes flattened due this crowding.For the PEI amine nitrogen atoms, the steric hindrance provided by thetwo or three extremely large substituents may impede even interactionwith small chemical entities, including the proton. It is, therefore,difficult to protonate all, or almost all of the amino groups imbeddedin the PEI backbone, so that the high nitrogen content of PEI is notmatched by a similarly high charge density (i.e., ammonium groups) oncethe volatile amine has evaporated from the coating. Furthermore, thoseamino groups that are protonated to form positively charged ammoniumgroups have reduced interaction with other chemical entities, again dueto very high steric hindrance afforded by the bulky substituent groups.

[0054] In order to destabilize the anionically stabilized emulsionpolymer of the coating composition, the highly hindered ammonium groupsof protonated PEI must make a very close approach to the anionic end ofan anionic surfactant molecule which itself is bulky due to the presenceof a large hydrophobic tail. The result is that, for many of theammonium groups that do form along the main chain of protonated PEI, therequisite very close approach is not possible, and those ammonium groupsare unable to participate in deactivating the anionic surfactantmolecules. As if this situation were not bad enough, PEI is actually nota linear polymer. The ratio of primary amino groups to secondary, totertiary is 1:2:1, so that approximately 25% of the nitrogen atoms aresurrounded by three bulky substituents, making those nitrogen atomsparticularly inaccessible as can be seen for the following tertiarynitrogen center:

[0055] Titration of PEI in water clearly demonstrates thisinaccessibility. Even at the very low pH of 2, only 75% of the nitrogensof PEI (i.e., a percentage equal to the percent of primary and secondarynitrogens present) are protonated. This titration data is available inthe Polymin™ (Polyethylenimine) product bulletin from BASF.

[0056] So, the promise of the high nitrogen content of PEI is notrealized as a correspondingly high number of destabilized anionicsurfactant molecules. Due to extremely high steric hindrance, only afraction of the amino groups can be converted to ammonium groups as thevolatile base evaporates, and many of those ammonium groups that do formare impeded from contact with anionic surfactant molecules, again due tosteric hindrance. Though not wishing to be bound by any particulartheory, we believe that, by contrast, pVAm is a linear polymer, havingprimary amino groups pendant to its backbone. Because they are primary,all of the nitrogen atoms of the amino groups are fully accessible forprotonation and the ammonium groups that result are fully accessible forinteraction with, and destabilization of anionic surfactants. In short,pVAm is more efficient than PEI, or any other polyamine functionalpolymer, at destabilization of anionically stabilized polymers. Thissuperior efficiency of destabilization leads directly to faster dryingrates for pVAm when compared with other polyfunctional amine polymers atequal weight percent concentration.

[0057] The binder polymer of the present invention can be any polymerthat can either be prepared as a dispersion in water, or be dispersed inwater after preparation. The composition of a binder polymer may be anycomposition that is characterized by a glass transition temperaturefalling in ranges specified herein above in the definition of “binderpolymer”. The specific method by which a binder polymer is prepared isnot of particular importance to the present invention. Binder polymersuseful in the compositions of the present invention may be prepared viabulk or solution polymerization; or by aqueous dispersion, suspension,or emulsion polymerization; or by any other method that would producethe desired polymer dispersed in water, or capable of being dispersed inwater. A preferred method for preparing the binder polymers to be usedin coating composition of the present invention is aqueous emulsionpolymerization. Polymers thus prepared are usually stabilized by addinganionic, nonionic, cationic, or amphoteric surfactants, or by theincorporation of anionic or cationic moieties into the polymer itselfduring synthesis. The emulsion polymerization can be carried out by anumber processes such as those described in Blackley, D. C. EmulsionPolymerisation; Applied Science Publishers: London, 1975; Odian, G.Principles of Polymerization; John Wiley & Sons: New York, 1991;Emulsion Polymerization of Acrylic Monomers; Rohm and Haas, 1967.

[0058] The aqueous emulsion polymer preferred as a binder polymer in thepresent invention is an addition polymer. The monomers from which theaddition polymer is formed are ethylenically-unsaturated. The aqueousemulsion polymer composition may be selected and the polymer prepared byconventional techniques known to those of ordinary skill in the art. Thepolymer may contain, as polymerized units, one or more ethylenicallyunsaturated monomers. Examples of these ethylenically unsaturatedmonomers include: C₁-C₂₂ linear or branched chain alkyl (meth)acrylates,bornyl (meth)acrylate, isobornyl (meth)acrylate, and the like;hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate;(meth)acrylamide or substituted (meth)acrylamides; styrene orsubstituted styrenes; butadiene; vinyl acetate or other vinyl ester;butylaminoethyl (meth)acrylate, di(methyl)aminoethyl (meth)acrylate; amonomer containing αβ-unsaturated carbonyl functional groups such asfumarate, maleate, cinnamate and crotonate; and (meth)acrylonitrile.Used herein, the word fragment “(meth)acryl” refers to both “methacryl”and “acryl”. For example, (meth)acrylic acid refers to both methacrylicacid and acrylic acid, and methyl (meth)acrylate refers to both methylmethacrylate and methyl acrylate.

[0059] Halocarbon monomers and siloxane monomers may also be used toprepare the binder polymers of the present invention. Halocarbonmonomers are monomers having bromo-, chloro-, or fluoro- sustituents, orcombinations thereof. Halocarbon monomers include, for example:2-bromoethyl (meth)acrylate; 4-bromostyrene; vinylidene chloride, vinylchloride; pentafluorophenyl (meth)acrylate; 2-(perfluoroalkyl)ethyl(meth)acrylates, including 2-(perfluorododecyl)ethyl (meth)acrylate, and2-(perfluorohexyl)ethyl (meth)acrylate; tetrafluoroethylene, andvinylidene fluoride.

[0060] A acid-functional monomers of the binder polymer of the presentinvention may also be present as polymerized units at preferably 0-10%by weight, based on the weight of the dry emulsion polymer.Acid-functional monomers useful in the present invention include, forexample, (meth)acrylic acid, itaconic acid, crotonic acid, phosphoethyl(meth)acrylate, sulfoethyl (meth)acrylate,2-acrylamido-2-methyl-1-propanesulfonic acid, fumaric acid, maleicanhydride, monomethyl maleate, and maleic acid.

[0061] Optionally, a low level of a multi-ethylenically unsaturatedmonomer may be incorporated into the polymer to provide crosslinking.The level of multi-ethylenically unsaturated monomer may be 0-5% byweight, based on the weight of the dry emulsion polymer. The upper limitis typically determined by the point at which film formation becomesimpaired. Useful multi-ethylenically unsaturated monomers include, forexample, allyl (meth)acrylate, diallyl phthalate, 1,4-butylene glycoldi(meth)acrylate, 1,6-hexanediol di(meth)acrylate, andtrimethylolpropane tri(methyl)acrylate.

[0062] Conventional surfactants may be used to stabilize the emulsionpolymerization systems before, during, and after polymerization ofmonomers. These conventional surfactants will usually be present atlevels of 0.1 percent to 6 percent by weight based on the weight oftotal monomer. At least one anionic, nonionic, or amphoteric surfactantmay be used, or mixtures thereof. Alternatively, all, or a portion, ofthe surfactant activity may be provided by initiator fragments, such asthose of persulfates, when the fragments become incorporated into thepolymer chain. Examples of anionic emulsifiers include sodium laurylsulfate, sodium dodecyl benzene sulfonate, dioctylsulfosuccinate, sodiumpolyoxyethylene lauryl ether sulfate, and sodium salt oftert-octylphenoxyethoxypoly(39)ethoxyethyl sulfate. Examples of nonionicsurfactants include glycerol aliphatic esters, oleic acid monoglyceride,polyoxyethylene aliphatic esters, polyoxyethylene glycol monostearate,polyoxyethylene cetyl ether, polyoxyethylene glycol monolaurate,polyoxyethylene glycol monooleate, polyoxyethylene glycol stearate,polyoxyethylene higher alcohol ethers, polyoxyethylene lauryl ether,polyoxyethylene nonylphenol ether, polyoxyethylene octylphenol ether,polyoxyethylene oleyl ether, polyoxyethylene stearyl ether,polyoxyethylenesorbitan aliphatic esters, polyoxyethylenesorbitanmonolaurate, polyoxyethylenesorbitan monooleate, polyoxyethylenesorbitanmonopalmitate, polyoxyethylenesorbitan monostearate,polyoxyethylenesorbitan trioleate, polyoxyethylenesorbitan tristearate,polyoxyethylenesorbitol tetraoleate, stearic acid monoglyceride,tert-octylphenoxyethylpoly(39)ethoxyethanol, andnonylphenoxyethylpoly(40)ethoxyethanol.

[0063] Amphoteric surfactants may also be utilized to stabilizeparticles of the polymer during and after aqueous emulsionpolymerization, or other dispersion polymerizations. For the purpose ofstabilizing particles of polymer in aqueous systems, amphotericsurfactants may be used at levels of 0.1 percent to 6 percent by weightbased on the weight of total monomer. Useful classes of amphotericsurfactant include aminocarboxylic acids, amphoteric imidazolinederivatives, betaines, and macromolecular amphoteric surfactants.Amphoteric surfactants from any of these classes may be furthersubstituted with fluorocarbon substituents, siloxane substituents, orcombinations thereof. Useful amphoteric surfactants can be found inAmphoteric Surfactants, ed. B. R. Bluestein and C. L. Hilton, SurfactantSeries Vol. 12 Marcel Dekker NY, N.Y.(1982).

[0064] Initiation of emulsion polymerization may be carried out by thethermal decomposition of free radical precursors, also called initiatorsherein, which are capable of generating radicals suitable for initiatingaddition polymerization. Suitable thermal initiators such as, forexample, inorganic hydroperoxides, inorganic peroxides, organichydroperoxides, and organic peroxides, are useful at levels of from0.05% to 5.0% by weight, based on the weight of monomers. Free radicalinitiators known in the art of aqueous emulsion polymerization includewater-soluble free radical initiators, such as hydrogen peroxide,tert-butyl peroxide; alkali metal (sodium, potassium or lithium) orammonium persulfate; or mixtures thereof. Such initiators may also becombined with reducing agents to form a redox system. Useful reducingagents include sulfites such as alkali metal meta bisulfite, orhyposulfite, sodium thiosulfate, or sodium formaldehyde sulfoxylate. Thefree radical precursor and reducing agent together, referred to as aredox system herein, may be used at a level of from about 0.01% to 5%,based on the weight of monomers used. Examples of redox systems includet-butyl hydroperoxide/sodium formaldehyde sulfoxylate/Fe(III) andammonium persulfate/sodium bisulfite/sodium hydrosulfite/Fe(III). Thepolymerization temperature may be 10° C. to 110° C., depending upon suchthings as free radical initiator decomposition constant and reactionvessel pressure capabilities.

[0065] Frequently, a low level of chain transfer agent such as amercaptan (for example: n-octyl mercaptan, n-dodecyl mercaptan, butyl ormethyl mercaptopropionate, mercaptopropionic acid at 0.05% to 6% byweight based on total weight of monomer) is employed to limit theformation of any significant gel fraction or to control molecularweight.

[0066] Used herein, the term “vinylamine polymer” refers topoly(vinylamine) homopolymer, vinylamine copolymers, N-substitutedpoly(vinylamine) homopolymers, N,N-disubstituted poly(vinylamine)homopolymers, N-substituted vinylamine copolymers, N,N-disubstitutedvinylamine copolymers, and combinations thereof. Unsubstitutedpoly(vinylamine) homopolymer is abbreviated “pVAm”, and isinterchangeably referred to herein as “poly(vinylamine)” or“poly(vinylamine) homopolymer”. Vinylamine copolymers may contain one ormore types of vinylamine monomer as polymerized units. Alternatively oradditionally, vinylamine copolymers may include, as polymerized units,monomers that are not vinylamine monomers. PVAm is available as Lupasol™LU 321 from BASF Corporation, Rensselaer, N.Y. The N-substituents ofN-substituted pVAms and N-substituted vinylamine copolymers, includelinear, branched, or cyclic alkyl groups having 1 to 6 carbons, andβ-hydroxyalkyl groups having 1 to 6 carbons. The vinylamine copolymersmust contain vinylamine monomer, N-substituted vinylamine monomer,N,N-substituted vinylamine monomer, or combinations thereof, present aspolymerized units, in an amount of, preferably 20 to 100 mole percent,more preferably 50 to 100 mole %, and most preferably 80 to 100 mole %of the vinylamine copolymer. All ranges specified herein are inclusiveand combinable. The N-substituents of N,N-disubstituted pVAms andN,N-disubstituted vinylamine copolymers include linear, branched, orcyclic alkyl groups having 1 to 6 carbons, β-hydroxyalkyl groups having1 to 6 carbons, and combinations thereof. Preferred vinylamine polymersare poly(vinylamine) homopolymer, poly(N-methylvinylamine),poly(N-ethylvinylamine), and poly(N-propylvinylamine). Most preferred ispoly(vinylamine) homopolymer. The monomers that are not vinylaminemonomers, or precursors to vinylamine functionality such asN-vinylformamide, that are useful in the preparation of vinylaminecopolymers may be any of the monomers listed herein above as useful inthe preparation of the binder polymer.

[0067] The vinylamine polymers of the present invention may be, ineither their fully protonated, partially protonated or fullydeprotonated forms, insoluble in water. Alternatively, they may besoluble or partially soluble in water when present at any degree ofprotonation. In the method of the present invention, the vinylaminepolymer may be applied to the surface of a substrate as part of theaqueous coating composition which includes an anionically stabilizedbinder polymer and a volatile base. Alternatively, the vinylaminepolymer may be applied as a component of an aqueous composition that isseparate from the aqueous composition containing the anionicallystabilized binder polymer. In the latter alternative, a volatile basemay, optionally, be present in the aqueous composition containing thevinylamine polymer. Vinylamine polymers may be prepared in a variety ofways, a few examples of which are found in the following references.U.S. Pat. No. 5,492,765 discloses preparation of vinylamine copolymers,for example, copolymers containing, as polymerized units, ethylene,vinyl alcohol and vinylamine derived from monomers including vinylacetate, ethylene, N-vinylformamide, and N-vinylacetamide. The aminogroups of these co-pVAms may be in ammonium ion form due to reactionwith mineral acid, or in non-ionic form, or in partially neutralizedform, depending upon pH. Weight average molecular weights (Mw) are inthe range 10,000-500,000. Re. 30,362, a reissue of U.S. Pat. No.4,018,826, discloses the preparation of pVAm salts of mineral acids fromvinylacetamide. U.S. Pat. No. 4,774,285 discloses N-vinylformamide(95-10 mole %) copolymerized with 5-90 mole % of ethylenicallyunsaturated monomers including: vinyl acetate, vinyl propionate; C1-C4alkyl vinyl ethers; esters, nitriles, and amides of (meth)acrylic acid;(meth)acrylic acid; and N-vinylpyrrolidone. U.S. Pat. No. 6,114,435discloses preparation of polymers containing N-vinylcarboxamide units.The N-vinylcarboxamide monomer includes N-vinylformamide,N-vinylmethylformamide, N-vinylacetamide, N-vinyl-N-methylacetamide,N-vinyl-N-ethylacetamide, N-vinylpropionamide,N-vinyl-N-methylpropionamide and N-vinylbutyramide. Followingpolymerization, hydrolysis leads to vinylamine polymers. U.S. Pat. No.6,057,404 discloses preparation of β-hydroxyalkylvinylamine polymers.U.S. Pat. No. 5,863,879 discloses preparation of N-substitutedvinylamine polymers wherein the substituent is C1-C6 alkyl. U.S. Pat.No. 5,280,077 discloses synthesis of oligomeric vinylamines havingmolecular weights in the range 600 to 2,500. The weight averagemolecular weight, M_(w), of the vinylamine polymer of the presentinvention may be 500 to 5,000,000, preferably 2,000 to 500,000, morepreferably 5,000 to 250,000, and most preferably 10,000 to 75,000.

[0068] The amount of vinylamine polymer useful in the present inventionis typically 0.25 to 40 weight percent, preferably 0.5 to 30 weight %,more preferably 1 to 20 weight %, and most preferably 2 to 10 weight %,based on the weight of the binder polymer.

[0069] The type and amount of volatile base used must be sufficient toraise the pH of the composition to about the point where thepolyfunctional amine is non-ionized (deprotonated), to avoid interactionwith the anionically stabilized emulsion. The volatile base ofpreference is ammonia, which may be used as the sole volatile base or inadmixture with other volatile or nonvolatile bases. Volatile basesuseful in the present invention include, for example, ammonia,morpholine, the lower alkyl amines, 2-dimethylaminoethanol,N-methylmorpholine, ethylenediamine, and others.

[0070] It is generally desirable to have additional components added tothe coating composition to form the final formulation for coatingcompositions, including traffic paints, described herein. Theseadditional components include, for example, thickeners; rheologymodifiers; dyes; sequestering agents; biocides; dispersants; pigments,such as, titanium dioxide, organic pigments, carbon black; extenders,such as calcium carbonate, talc, clays, silicas and silicates; fillers,such as glass or polymeric microspheres, quartz and sand; anti-freezeagents; plasticizers; adhesion promoters such as silanes; coalescents;wetting agents; surfactants; slip additives; crosslinking agents;defoamers; colorants; tackifiers; waxes; preservatives; freeze/thawprotectors; corrosion inhibitors; and anti-flocculants. Duringapplication of the aqueous coating composition of the present inventionto the surface of a substrate, glass or polymeric microspheres, quartzand sand may be added as part of the that coating composition or as aseparate component applied to the surface in a separate stepsimultaneously with, before, or after the step of application of theaqueous coating composition.

[0071] During application of the aqueous coating composition of thepresent invention to the surface of a substrate, “absorbers” may beadded as a separate component applied to the surface in a separate stepsimultaneously with, before, or after the step of application of theaqueous coating composition. Used herein, the term “absorber” refers tothe general class of materials that includes hollow sphere polymer, ionexchange resin beads (e.g., in acid form, in base form, in salt form, inpartially neutralized form, or in mixed salt form), and absorbentinorganic compounds (e.g., inorganic superabsorbent gel, Sumica gel),including talc. Other “absorbers” useful in the present invention aremolecular sieves, non-porous carbonaceous materials, porous carbonaceousmaterials, and superabsorbent polymers (abbreviated SAP or SAPs herein).These absorber are capable of further increasing the drying rate of theaqueous coating compositions of the present invention.

[0072] The aqueous coating compositions of the present inventioninclude, for example, interior house paints, exterior house paints,automotive paints, appliance paints, and traffic paints. The preferreduse of the aqueous coating composition of the present invention is as atraffic paint which can be applied to a roadway surface to form aroadway marking.

EXPERIMENTAL

[0073] Lupasol™ LU 321 is a high molecular weight poly(vinylamine)available from BASF Corporation of Rensselaer, N.Y.

[0074] Molecular Weight Determination using Gel PermeationChromatography (GPC)

[0075] Gel Permeation Chromatography, otherwise known as size exclusionchromatography, actually separates the members of a distribution ofpolymer chains according to their hydrodynamic size in solution ratherthan their molar mass. The system is then calibrated with standards ofknown molecular weight and composition to correlate elution time withmolecular weight. The techniques of GPC are discussed in detail inModern Size Exclusion Chromatography, W. W. Yau, J. J Kirkland, D. D.Bly; Wiley-Interscience, 1979, and in A Guide to MaterialsCharacterization and Chemical Analysis, J. P. Sibilia; VCH, 1988,p.81-84.

[0076] For example, the molecular weight information for a low molecularweight sample (e.g., 10,000) may be determined as follows: The sample(an aqueous emulsion containing low molecular weight particles) isdissolved in THF at a concentration of approximately 0.1% weight sampleper volume THF, and shaken for 6 hours, followed by filtration through a0.45 μm PTFE (polytetrafluoroethylene) membrane filter. The analysis isperformed by injecting 100 μl of the above solution onto 3 columns,connected in sequence and held at 40° C. The three columns are: one eachof PL Gel 5 100, PL Gel 5 1,000, and PL Gel 5 10,000, all available fromPolymer Labs, Amherst, Mass. The mobile phase used is THF flowing at 1ml/min. Detection is via differential refractive index. The system iscalibrated with narrow polystyrene standards. PMMA-equivalent molecularweights for the sample are calculated via Mark-Houwink correction usingK=14.1×10⁻³ ml/g and a=0.70 for the polystyrene standards and K=10.4×10⁻³ ml/g and a=0.697 for the sample.

[0077] Dry Through Tests

[0078] Each test paint is applied to a 4″ (10.2 cm)×12″ (30.5 cm) glasspanel using a drawdown blade having a gap of 500μ, (20 mils).

[0079] After application of the coating, the panels are immediatelyplaced in a high humidity test chamber supplied by Victor Associates,Inc. (Hatboro, Pa.), maintained at a relative humidity of 90%±3%. Thistest chamber is equipped with a certified hygrometer and temperatureindicator, both of which are fastened to the center of the rear wall ofthe test chamber to ensure balanced measurement. The 90%±3% relativehumidity is obtained by filling the pan at the bottom of the completelyclosed test chamber with a 1 inch layer of water, equilibrating thechamber overnight (about 16 hours) before testing (bringing the relativehumidity inside the chamber to 100%), and then adjusting the size of theside port openings to achieve a relative humidity of 90%±3% within thechamber. The temperature inside the test chamber is 23° C. (74° F.).

[0080] The door of the test chamber is opened briefly at 5-minuteintervals to evaluate the dry-through time for the paint test panel.Dry-through time is defined as the time it takes for a wet paint film toreach a state such that the paint cannot be distorted with a 90° thumbtwist when the thumb is touching the paint surface, but no pressure isbeing applied. During the early stages of drying, dry through isassessed by pushing a small applicator stick through the surface of thefilm to the substrate, and then gauging the dryness of the coating inthe lower layer by dragging the applicator stick along the substrate fora length of approximately 0.5 inch (˜1.27 cm). As it becomes clear thatthe coating is approaching a dried through state, the panel is thenremoved from the box at the appropriate time, and the aforementioned 90°thumb twist test is conducted.

Example 1 Preparation of an Aqueous Coating Composition Containing aBinder Polymer, a Vinylamine Polymer and a Volatile Base

[0081] To a 5-liter reactor containing 1224.6 g deionized water (DIwater) under a nitrogen atmosphere at 81° C., 4.7 g of sodiumdodecylbenzene sulfonate (23% active), 67.7 g of monomer emulsion,disclosed in table I below, 3.2 g of sodium carbonate dissolved in 60 gDI water and 3.2 g ammonium persulfate dissolved in 50 g DI water areadded with stirring. The remainder of the monomer emulsion No. 1 and asolution of 3.2 g ammonium persulfate dissolved in 100 g DI water aregradually added over a period of 162 minutes. At the end of the feed, 50g of DI water is added to rinse the monomer emulsion feed line. Aftercooling to 60° C., 9.0 g of an aqueous solution of ferrous sulfateheptahydrate (0.15%), 1.6 g t-butylhydroperoxide dissolve in 20 g DIwater and 0.8 g of sodium sulfoxylate formaldehyde didhydrate dissolvedin 20 g DI water are added. Ammonium hydroxide (28%) is added to raisethe pH to approximately 10.7 after which is added 180 g ofpoly(vinylamine) solution (12% by weight, based on the total weight ofaqueous solution). The weight average molecular weight, Mw, of thebinder polymer should be 250,000 as determined by gel permeationchromatography. TABLE I Composition of Monomer Emulsion No. 1 IngredientEmulsion No Weight in grams DI water 541.1 sodiumdodecylbenzenesulfonate 19.7 (23 percent by weight in water) butylacrylate 1080.0 methyl methacrylate 1051.9 methacrylic acid 28.1

Comparative Example A Preparation of an Aqueous Coating CompositionContaining a Binder Polymer, a Volatile Base, but no Vinylamine Polymer

[0082] To a 5-liter reactor containing 1224.6 g deionized water (DIwater) under a nitrogen atmosphere at 81° C., 4.7 g of sodiumdodecylbenzene sulfonate (23% active), 67.7 g of monomer emulsion,disclosed in Table I above, 3.2 g of sodium carbonate dissolved in 60 gDI water and 3.2 g ammonium persulfate dissolved in 50 g DI water areadded with stirring. The remainder of the monomer emulsion No. 1 and asolution of 3.2 g ammonium persulfate dissolved in 100 g DI water aregradually added over a period of 162 minutes. At the end of the feed, 50g of DI water is added to rinse the monomer emulsion feed line. Aftercooling to 60° C., 9.0 g of an aqueous solution of ferrous sulfateheptahydrate (0.15%), 1.6 g t-butylhydroperoxide dissolve in 20 g DIwater and 0.8 g of sodium sulfoxylate formaldehyde didhydrate dissolvedin 20 g DI water are added. Ammonium hydroxide (10.5 g of a 28% aqueoussolution) is added. The weight average molecular weight, Mw, of thebinder polymer should be 250,000 as determined by gel permeationchromatography.

Example 2 Preparation of an Aqueous Coating Composition Containing aBinder Polymer, a Vinylamine Polymer and a Volatile Base

[0083] To a 5-liter reactor containing 1257.0 g deionized water (DIwater) under a nitrogen atmosphere at 81° C., 4.7 g of sodiumdodecylbenzene sulfonate (23% active), 67.7 g of monomer emulsion,disclosed in Table II below, 3.2 g of sodium carbonate dissolved in 60 gDI water and 3.2 g ammonium persulfate dissolved in 50 g DI water areadded with stirring. The remainder of the monomer emulsion No. 2 and asolution of 3.2 g ammonium persulfate dissolved in 100 g DI water aregradually added over a period of 162 minutes. At the end of the feed, 50g of DI water is added to rinse the monomer emulsion feed line. Aftercooling to 60° C., 9.0 g of an aqueous solution of ferrous sulfateheptahydrate (0.15%), 1.6 g t-butylhydroperoxide dissolve in 20 g DIwater and 0.8 g of sodium sulfoxylate formaldehyde dihydrate dissolvedin 20 g DI water are added. Ammonium hydroxide (28%) is added to raisethe pH to approximately 10.8 after which is added 135 g ofpolyvinylamine solution (12%). The weight average molecular weight, Mw,of the binder polymer should be 40,000 as determined by gel permeationchromatography. TABLE II Composition of Monomer Emulsion No. 2Ingredient Emulsion No Weight in grams DI water 541.1 sodiumdodecylbenzenesulfonate 19.7 (23 percent by weight in water) butylacrylate 1080.0 methyl methacrylate 1051.9 methacrylic acid 28.1n-dodecyl mercaptan 32.4

Comparative Example B Preparation of an Aqueous Coating CompositionContaining a Binder Polymer, a Volatile Base, but no Vinylamine Polymer

[0084] To a 5-liter reactor containing 1257.0 g deionized water (DIwater) under a nitrogen atmosphere at 81° C., 4.7 g of sodiumdodecylbenzene sulfonate (23% active), 67.7 g of monomer emulsion,disclosed in Table II above, 3.2 g of sodium carbonate dissolved in 60 gDI water and 3.2 g ammonium persulfate dissolved in 50 g DI water areadded with stirring. The remainder of the monomer emulsion No. 2 and asolution of 3.2 g ammonium persulfate dissolved in 100 g DI water aregradually added over a period of 162 minutes. At the end of the feed, 50g of DI water is added to rinse the monomer emulsion feed line. Aftercooling to 60° C., 9.0 g of an aqueous solution of ferrous sulfateheptahydrate (0.15%), 1.6 g t-butylhydroperoxide dissolve in 20 g DIwater and 0.8 g of sodium sulfoxylate formaldehyde dihydrate dissolvedin 20 g DI water are added. Ammonium hydroxide (10.5 g of a 28% aqueoussolution) is added. The weight average molecular weight, Mw, of thebinder polymer should be 40,000 as determined by gel permeationchromatography.

Examples 3 and 4, and Comparative Examples C and D Preparation of Paintsfrom Aqueous Coating Composition.

[0085] To examples 1 and 2, and comparative examples A and B, thefollowing components are added in the order shown in Table III toprepare the pre-mixes for examples 3 and 4, and comparative examples Cand D: TABLE III Ingredients used to prepare pre-mixes for Examples 3and 4 and Comparative Examples C and D. Comp. Comp. Example 3 Example 4Example C Example D Ingredient pre-mix pre-mix pre-mix pre-mix Example 1433.3 Example 2 433.3 Comparative 433.3 Example A Comparative 433.3Example B DI water 20.7 20.7 20.7 20.7 Dispersant¹ 5.4 5.4 5.4 5.4Surfactant² 2.9 2.9 2.9 2.9 Defoamer³ 2.1 2.1 2.1 2.1 White pigment⁴103.4 103.4 103.4 103.4 Extender⁵ 786.5 786.5 786.5 786.5

[0086] The components of Table III are mixed for 10 minutes or untilsmooth (the fineness of the grind as tested according to ASTM D1210 ofnot less than 3 Hegmen units) to form a mix to which the followingcomponents are added, in the order shown in Table IV, with continuousmixing: TABLE IV Ingredients used to prepare Examples 3 and 4 andComparative Examples C and D. Comp. Comp. Ingredient Example 3 Example 4Example C Example D Example 3 pre-mix 1354.3 Example 4 pre-mix 1354.3Comparative 1354.3 Example C pre-mix Comparative 1354.3 Example Dpre-mix methanol 25.8 25.8 25.8 25.8 coalescing solvent⁶ 19.2 19.2 19.219.2 defoamer³ 3.6 3.6 3.6 3.6

[0087] TABLE V Dry- through Empl. Paint Formulation Time^(a) DrawdownNo. vinylamine polymer (from Table IV) (min.) gap 5 noneComparative >180 20 mils Example C 6 none Comparative >180 20 milsExample D 7 poly(vinylamine) Example 3 45 20 mils 8 poly(vinylamine)Example 4 45 20 mils

I claim:
 1. A storage stable, fast drying aqueous coating composition,said composition comprising: (a) an anionically stabilized binderpolymer; (b) a vinylamine polymer having from 20% to 100% by weight ofamine functional units, based on total weight of said vinylaminepolymer; and (c) an amount of volatile base sufficient to raise the pHof said composition to a point where essentially all of the amine groupsof said vinylamine polymer are in a non-ionic state.
 2. The compositionof claim 1, wherein said binder polymer has a glass transitiontemperature of −10° C. to 70° C.
 3. The composition of claim 1, whereinsaid vinylamine polymer is a vinylamine polymer selected from the groupconsisting of poly(vinylamine) homopolymer, vinylamine copolymers,N-substituted poly(vinylamine) homopolymers, N,N-disubstitutedpoly(vinylamine) homopolymers, N-substituted vinylamine copolymers,N,N-disubstituted vinylamine copolymers, and combinations thereof. 4.The composition of claim 1, wherein said vinylamine polymer ispoly(vinylamine) homopolymer.
 5. The composition of claim 1, whereinsaid composition is a traffic paint.
 6. A coating on the surface of asubstrate, said coating comprising: (a) an anionically stabilized binderpolymer; and (b) a vinylamine polymer having from 20% to 100% by weightof amine functional units, based on total weight of said vinylaminepolymer.
 7. The coating of claim 6, wherein said binder polymer has aglass transition temperature of −10° C. to 70° C.
 8. The coating ofclaim 6, wherein said vinylamine polymer is a vinylamine polymerselected from the group consisting of poly(vinylamine) homopolymer,vinylamine copolymers, N-substituted poly(vinylamine) homopolymers,N,N-disubstituted poly(vinylamine) homopolymers, N-substitutedvinylamine copolymers, N,N-disubstituted vinylamine copolymers, andcombinations thereof.
 9. The coating of claim 6, wherein said vinylaminepolymer is poly(vinylamine) homopolymer.
 10. The coating of claim 6,wherein said coating is a roadway marking and said substrate is aroadway.
 11. A method of producing a coating on the surface of asubstrate, said method comprising the steps of: (i) applying to saidsurface a fast drying aqueous coating composition comprising: (a) ananionically stabilized binder polymer; (b) a vinylamine polymer havingfrom 20% to 100% by weight of amine functional units, based on totalweight of said vinylamine polymer; and (c) an amount of volatile basesufficient to raise the pH of said composition to a point whereessentially all of the amine groups of said vinylamine polymer are in anon-ionic state; (ii) evaporating said volatile base from saidcomposition; and (iii) drying said composition to form said coating. 12.The method of claim 11, wherein said binder polymer has a glasstransition temperature of −10° C. to 70° C.
 13. The method of claim 11,wherein said vinylamine polymer is a vinylamine polymer selected fromthe group consisting of poly(vinylamine) homopolymer, vinylaminecopolymers, N-substituted poly(vinylamine) homopolymers,N,N-disubstituted poly(vinylamine) homopolymers, N-substitutedvinylamine copolymers, N,N-disubstituted vinylamine copolymers, andcombinations thereof.
 14. The method of claim 11, wherein saidvinylamine polymer is poly(vinylamine) homopolymer.
 15. The method ofclaim 11, wherein said coating is a road marking and said substrate is aroadway.
 16. A method of producing a coating on the surface of asubstrate, said method comprising the steps of: (i) applying to saidsurface an aqueous composition comprising an anionically stabilizedbinder polymer; (ii) applying to said surface an aqueous compositioncomprising a vinylamine polymer having from 20% to 100% by weight ofamine functional units, based on total weight of said vinylaminepolymer; and (iii) drying said coating.
 17. The method of claim 16,wherein said aqueous composition comprising a vinylamine polymer furthercomprises an amount of volatile base sufficient to deprotonate 20% to100% of the amine groups of said vinylamine polymer; and wherein saidmethod further comprises the step of evaporating said volatile base fromsaid coating.
 18. A storage stable, fast drying aqueous coatingcomposition, said composition comprising: (a) an anionically stabilizedbinder polymer; (b) a vinylamine polymer having from 20% to 100% byweight of amine functional units, based on total weight of saidvinylamine polymer; and (c) an amount of volatile base sufficient todeprotonate 20% to 100% of the amine groups of said vinylamine polymer.19. A method of producing a coating on the surface of a substrate, saidmethod comprising the steps of: (i) applying to said surface a fastdrying aqueous coating composition comprising: (a) an anionicallystabilized binder polymer; (b) a vinylamine polymer having from 20% to100% by weight of amine functional units, based on total weight of saidvinylamine polymer; and (c) an amount of volatile base sufficient todeprotonate 20% to 100% of the amine groups of said vinylamine polymer;(ii) evaporating said volatile base from said composition; and (iii)drying said composition to form said coating.